Per our phone discussion with Misha, here is a plan on how Cayenne
configuration should look like:
1. Project file - GUI support only, no role in deployment (details to be
defined)
2. Domain XML file(s) (see sample in the bottom of this message, and a
CVS version at cayenne/doc/cayenne.xml) - deployed with the application
in standard location. File URI is preset : "cayenne.xml". Lookup for
this file is performed in CLASSPATH (for example it can be in a root of
a JAR file). No lookup in current directory, or user home directory,
etc. is performed, since this location must be portable for any kind of
deployment.
3. Map XML file(s) - deployed with the application. Location is
determined from Domain file. Lookup is done the same way domain lookup
is done (via CLASSPATH using ClassLoader)
4. Data node XML resource(s) (usually a file) - these are NOT deployed
with application. Rather an application needs a way to find them. This
is done using 2 pieces of information - relative location string in
domain file and factory class name. Instantiated factory class will know
how to read node configuration using location string. At the moment we
are planning to implement NodeJNDIFactory (resolves path via JNDI
context provided by container), and NodeFileFactory (resolves path
relative to known locations - current directory, user home directory,
CLASSPATH - good for deployments without a container, like standalone
applications). Final names and packages of the factory classes are yet
to be determined.
This way datanodes (or rather their datasources) will be provided by
deployment environment (either a webapplication container or just a
server where the code is deployed). Deployment configuration is minimal,
and is not affected by development changes and new releases.
... finally we got a plan ... :-)
======================================
<?xml version="1.0" encoding="utf-8"?>
<!-- sample domain config file. -->
<datadomains>
<domain name="domain1">
<map name="m11" location="m11.xml"/>
<map name="m12" location="dir/m12.xml"/>
<!-- DataNode connection information is taken from the XML file -->
<node name="dn11"
location="n11.xml"
factory="org.objectstyle.cayenne.access.NodeFileFactory">
<map name="m11"/>
</node>
<!-- DataNode connection information is resolved via JNDI -->
<node name="dn12"
location="nodes/n11"
factory="org.objectstyle.cayenne.access.NodeJNDIFactory">
<map name="m12"/>
</node>
</domain>
<domain name="domain2">
<map name="m21" location="m11.xml"/>
<map name="m22" location="dir/m12.xml"/>
<!-- DataNode connection information is taken from the XML file -->
<node name="dn21"
location="n21.xml"
factory="org.objectstyle.cayenne.access.NodeFileFactory">
<map name="m21"/>
</node>
<!-- DataNode connection information is resolved via JNDI -->
<node name="dn22"
location="nodes/n22"
factory="org.objectstyle.cayenne.access.NodeJNDIFactory">
<map name="m22"/>
</node>
</domain>
</datadomains>
-- ~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~- - Andrei (a.k.a. Andrus) Adamchik http://objectstyle.org email: andrus at objectstyle dot org
This archive was generated by hypermail 2.0.0 : Tue Mar 05 2002 - 22:43:22 EST